1. Field of the Invention
The present invention relates to a novel cationic dye for dyeing acid modified polyacrylonitrile, polyester and polyamide fibers.
2. Description of the Prior Art
A number of blue cationic dyes of naphthostyril series with a high fastness to heat have been known; none of them, however, are satisfactory as a three-primary color dye which is in large demand. While the well known dyes disclosed in Japanese Patent Publication No. 20714/1966 or 30070/1970 can dye polyacrylonitrile fibers a clear blue shade with high fastness, they have disadvantages in that the high dyeing velocity thereof deteriorates the compatibility which is one of the most important properties of cationic dyes. Therefore an improvement in the dyeing velocity of those blue dyes has been a serious problem in the field of dyeing.